The power control of conventional mobile devices has been typically designed to function in a conservative manner. As a result, timeouts may often be used to lower resources usage. However, such timeouts may often be lengthy and they often may sacrifice power to favor performance for such conventional mobile devices. For example, power control in a conventional mobile phone may typically involve constantly examining sufficiency of specific performance metrics to measure whether it may be warranted for resources to be reduced, or conversely increase resources when performance could be anticipated to become deficient. The generic performance metrics that may be commonly used to measure workload processing performance may include attributes like idleness of the processors, bus arbitration exception rate or bus bandwidth. After measuring such performance metrics, conventional power control methods may speculate future resources level without knowing how platform workload or concurrency may change, often risking resources to become too scarce or too much. Such call-back schemes that require constantly measuring platform resource sufficiency can be inherently costly and unaffordable for always-on wearable devices with small battery capacity, such as wrist-worn watches or head-mount displays.
In addition, battery used in a typical conventional mobile device may have capacity of approximately 2000 mA-Hour. On the other hand, battery used in a wearable mobile device may have capacity that cannot exceed approximately 50 mA-Hour, with similar type, volume, and weight density of battery as used in the conventional mobile device. Moreover, since a wearable mobile device can be expected to be constantly worn and in-touch with a user, it may be desirable for the wearable mobile device to be always-on to enable many essential applications, such as health, security, surveillance applications. In such situations, it can be even more critical to enable power control and access control to such wearable mobile devices. Therefore, it would be beneficial to control power and performance more efficiently for such wearable mobile devices.